Apraclonidine (2-[(4-amino-2,6-dichlorophenyl)imino]imidazolidine monohydrochloride or para-amino clonidine) is known to be effective in lowering intraocular pressure (IOP) in persons suffering from glaucoma or ocular hypertension. See, U.S. Pat. No. 4,517,199, which is incorporated herein by reference. It is also useful in preventing IOP spikes which commonly occur during or following intraocular surgery. See, U.S. Pat. No. 5,212,196, which is incorporated herein by reference. Iopidine.RTM. 0.5% is an apraclonidine ophthalmic solution available from Alcon Laboratories, Inc., Fort Worth, Tex. It is indicated for short term adjunctive therapy in patients on maximally tolerated medical therapy who require additional IOP reduction. Iopidine.RTM. 1% is an apraclonidine solution, also available from Alcon Laboratories, Inc., indicated to control or prevent post surgical elevations in intraocular pressure. Iopidine.RTM. is contraindicated for patents with hypersensitivity to apraclonidine or any other component of the medication.